64785409 has 12 divisors (see below), whose sum is σ = 71850324. Its totient is φ = 58027104.

The previous prime is 64785403. The next prime is 64785431. The reversal of 64785409 is 90458746.

It can be written as a sum of positive squares in 2 ways, for example, as 34480384 + 30305025 = 5872^2 + 5505^2 .

It is not a de Polignac number, because 64785409 - 2¹³ = 64777217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64785403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 176344 + ... + 176710.

It is an arithmetic number, because the mean of its divisors is an integer number (5987527).

Almost surely, 2^64785409 is an apocalyptic number.

It is an amenable number.

64785409 is a deficient number, since it is larger than the sum of its proper divisors (7064915).

64785409 is an equidigital number, since it uses as much as digits as its factorization.

64785409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 43.

The square root of 64785409 is about 8048.9383772023. The cubic root of 64785409 is about 401.6296205759.

The spelling of 64785409 in words is "sixty-four million, seven hundred eighty-five thousand, four hundred nine".